Put a 500-pF variable capacitor in series with the link inside or, outside
the enclosure in series with the center conductor of the coax line feeding
the JMBox. Gives you an extra degree of freedom in tuning.
73, Dave, N3HE

SNIP
between the rig and the matching device. The only problem with using
the Johnson Matchbox is 30M

73 de n4jvp
Fritz